Plugging the drain

April 20 2003

Melbourne can avoid a dry future - if it embraces a new philosophy on water use. Melissa Fyfe reports.

In the hills behind Warburton, a drop of water falls from a myrtle leaf to O'Shannassy Creek. The sun, finding its way here to the feet of tree-giants, hits the drop and makes it diamond-like. This is the beginning of its seven-year journey to your tap.

In the locked-up mountain ash forests of Melbourne's catchments, water seems a simple thing. But when it reaches the city, that drop becomes a subject of considerable hand-wringing.

Water is emotive. Talkback radio crackles with fury at water wasters. Councils are castigated for reckless use of automatic sprinklers. CityLink is despised for, until recently, using drinking water at the Burnley Tunnel. And Melbourne Water managing director Brian Bayley sometimes faces public grillings that would daunt the most polished corporate performer.

Much of this angst is sparked by drought, water restrictions and the city's ever-emptying dams, now 43 per cent full. But this is not a crisis: it is a planned-for and expected drought - a severe one, yes - that happens, on average, every 20 years in Melbourne.

It may take a few years to replenish the dams when the drought finally breaks. Once full, however, Melbourne's water storages are an impressive asset. If, by some strange fate, it stopped raining, the city could survive on its storages for three-and-a-half years.");document.write("

advertisement

");
}
}
// -->

No, this is not a crisis. A crisis is what the city will face in about 12 years, when, on current water-use trends and with an increased population, it will literally run out of water.

This looming shortage has spurred a major rethink of Melbourne's water supply. An exhaustive strategy, commissioned by the State Government, was released late last year.

The strategy aims to make Melbourne's water resources cover the Department of Infrastructure's estimated 32 per cent increase in population by 2050 (some believe the city should fit its population to its resources, not the other way around).

The strategy's starting point is no new dam. Dams are pretty unfashionable these days - economically and environmentally. The 50-year plan allows for the reconnection of an unused dam, but otherwise caps the city's bucket of water. The water savings will come from residents, who are being asked to cut their use by 15 per cent.

Emeritus Professor Nancy Millis, chairwoman of the Water Resources Strategy, explains what is at stake: "If people do not respond, either we are going to have draconian regulations . . . or we are going to have to build another dam.

"That will be at a very great environmental and financial cost and I will be very, very sorry if we haven't been disciplined enough to do this by a process that does not involve a lot of frequent and draconian regulation."

When Professor Millis gathered her Water Resources Strategy Committee, several options were on the table. While Melbourne's current water supply capacity is 566,000 million litres, the committee was actually playing with a possible resource of 675,000 million litres. This amount is theoretically available, but getting it into Melbourne's system would have an impact on streams - particularly the Yarra River - and require more infrastructure such as larger pipes and pumping systems.

There are other possibilities. Diverting water from the Big River to the Upper Yarra dam, for example, would give Melbourne an extra 80,000 million litres. But this would upset farmers whose water rights would have to be bought.

So the committee recommended only one boost to Melbourne's supply, and its preferred option was reconnecting the Tarago reservoir in the city's east. Tarago has an open catchment and is susceptible to pollution. It was deemed unnecessary and disconnected from the system, but could be used if a $20 million treatment plant was built for it.

Melburnians - and 1.12 million new Melburnians by 2050 - must therefore squeeze their water consumption under this ceiling of 570,000 million litres a year. To understand what this means, let's fast forward to the Water Resources Strategy vision for the year 2050.

The biggest water saving in 2050 - 27,000 million litres a year - comes from a humble place: the laundry. By 2010, the State Government made it compulsory to replace top-loading washing machines with front loaders.

Some top loaders used as much as 26 to 34 litres of water for a kilogram of clothes, but front loaders use as little as eight to 12 litres.

In 2050, 90 per cent of homes have AAA shower roses. The State Government made them compulsory in 2005. By 2050 this is saving the city 20,000 million litres a year, or 2.3 litres per minute of shower time.

We're also more into rain tanks and grey-water systems in 2050. Golf courses and councils never dream of using drinking water to keep things green. Recycled water is a cheaper option, and councils tap into sewers and treat effluent to a standard almost good enough to drink.

Councils let nature and median strips brown off in summer, thereby escaping the wrath of ratepayers. In 2050 the City of Melbourne has replaced most of its grass with a drought-resistant variety.

People still grow roses and tomatoes, but more efficiently, saving 4000 million litres of water a year. People who water pavements are looked upon as social outcasts and fined.

In 2050 the city's sporting venues have worked out how to harvest rainwater and new apartment blocks gather grey water in the basement, treat it, and return it for flushing toilets.

New subdivisions are water-friendly, with "third pipes" delivering treated grey water - filtered through nearby wetlands - back to the houses for non-drinking uses. Also, there are many more flats in Melbourne, which use much less water than houses.

Generally, people are thinking more about water, not just because there seems less in 2050 - climate change having kicked in - but also because it is more expensive. By 2050, Melbourne has better water-pricing policies which will see households charged if they use more water than is deemed appropriate for the number of people in the home.

The water industry has come into line with the energy industry and charges more for peak times, such as summer.

The Water Resources Strategy was an informed and exhaustively consultative process, but not without its critics. In fact, one of them sat on the committee: the Australian Conservation Foundation's land and water campaigner, Tim Fisher.

"The report was in some ways a compromise and, in my view, could have gone a lot further, especially on issues like opportunities for water recycling and reuse, capture of urban stormwater and better meeting the needs of the environment," says Fisher. "I think it would have been a stronger report had the process been genuinely independent from Melbourne's water agencies."

The strategy does have one glaring omission: it has failed to put aside future water to improve environmental flows for the creeks and streams affected by Melbourne's thirst.

Melbourne's Water's Brian Bayley believes Melburnians would be upset if they thought their water use was having an environmental impact.

"People these days want to think they are doing good things for the environment and I would be pretty offended if I though that me getting my water was having a major impact on the environment," he said.

"Major impact" can often be a subjective judgement, but it is clear that Melbourne's water use affects the environment in three main ways.

The most obvious is waste. From the pristine catchments, 281,000 million litres of water each year ends up in the sewerage system and in Port Phillip Bay or Bass Strait. Melbourne's eastern sewage outfall has degraded the Boags Rocks environment near Gunnamatta beach, and even when effluent quality improves, fresh water is still toxic to a marine environment. The less water we use - and the more we recycle - the smaller this impact.

Perhaps less obvious is the impact on the Yarra. The University of Melbourne's Brian Findlayson, a leading river expert, says what happened to the Yarra is not unlike what happened to the Snowy when it was dammed.

When the Upper Yarra reservoir was built in 1957, the Yarra was essentially turned off, says Findlayson, and became a river in two parts. The lower Yarra gets no water released from the dam, but does get water from the tributaries that run into it downstream. Like the lower Snowy, the Yarra now has only half its natural flow.

Findlayson wants to see more water for the Yarra - but done in a set of releases that are designed for ecological benefit.

Tim Fisher agrees. "The Yarra has a number of floodplain and wetland areas that used to support some really important natural values. There are no watering regimes for those wetlands at the moment," says Fisher, nominating the Christmas Hills, Bulleen and Banyule areas. "There is an assumption in Melbourne's water agencies that the Yarra and its water resources belongs to them. It doesn't . . . the fact we've modified to the point that we have does not give us a right to trash it further."

The third environmental impact is the most sensitive for Melbourne Water: Gippsland's Thomson River. The massive Thomson dam was finished in 1983 and, when full, stores more water for Melbourne than all of the other reservoirs combined. The reservoir forever changed the Thomson, diverting 53.5 per cent of its flows at the dam to Melbourne. Studies have found that the dam is responsible for a loss of species. The Victorian Water Resources Data Warehouse rates the river as poor or very poor below the dam.

Melbourne Water cannot take the blame for all of the Thomson's woes - irrigators also take water. And it isn't solely responsible for the ill-health of the Gippsland Lakes, into which the Thomson flows. A $600,000 CSIRO study found the lakes' problems were more to do with farming nutrients than reduced inflows.

Still, Gippsland resident Duncan Malcolm, chairman of water group Watermark and the Gippsland Coastal Board, believes that increased flows in the Thomson are necessary. "There is still an enormous amount of resentment that so much water goes out of this catchment and into Melbourne, there is no question about that," says Malcolm.

An expert panel is looking at the Thomson's environmental flow, and the 10th flow study in 20 years has just been completed. Experts such as Findlayson - who sits on the panel - want the environmental flows to be smarter, to provide more natural peaks and flushes. These could even be advertised to kayakers, he said.

Findlayson wants to see Melbourne Water commit to a better environmental flow regime, and to monitor it. If this had been done 10 years ago, experts would now have better information to make decisions about flows, he says. This will become crucial when Melbourne's water resources are squeezed. "That's when the whole environmental issue is going to get fairly serious."

Brian Bayley agrees that environmental flows should better reflect the natural pulse of the river, but is uncomfortable putting a price on what increased flows down the Thomson would cost Melbourne Water: the 125 million litres currently released from the dam each day is $44,000 worth of water in Melbourne.

"People have said (the Thomson) is a sick river," says Bayley. "I don't know if that is true or not true and what the science is behind all of that. I would really like to see what does us putting (more) water down there do? What is the health of it now and how do you address it?"

Ask Bayley why you should save water and he won't mention increased environmental flows. Instead, he talks of future strains on resources and not building another dam.

But Tony Kelly, managing director of water retailer Yarra Valley Water, says population increase is only half the story. "I think we have to make sure that we do allocate water to those areas that are stressed - and have the potential to become stressed - so they are preserved for future generations. That will end up lowering the yield of the existing water supply because we are allocating more to the environment and less to the community."

The potential to improve the environment, says Kelly, would give Melburnians more incentive to conserve water.

So what will push us to save water now? And can it be done?

History shows us that it can. Twenty years ago, per-capita city water use was increasing at 3 per cent a year. But user-pays pricing and water-saving campaigns have driven consumption increases down to 1 per cent a year.

Most famous of these campaigns were the "Don't be a Wally" TV ads featuring comedian Peter Moon.

Without this drop in use, Melbourne would now be close to running dry. "If we had kept going at 3 per cent we would be out there now digging another dam," says Bayley.

But we are still among the most water-greedy people in the world. The CSIRO's Peter Dillon points out that only Americans use more water than Australians. "We use about twice, per capita, the water that France, Germany and the United Kingdom use and 10 times what the World Health Organisation says each human needs," Dillon says.